Study Stash for Canvas reads your Canvas courses (what's due, assignments and rubrics, your submissions and feedback, modules, files, pages and announcements) and sends them to your own Study Stash library, on a computer you control. They go nowhere else: not to the developers, not to any third party. There is no analytics.

It uses your own Canvas sign-in. It never sees your Canvas password and never reads your cookies: the browser sends them to Canvas as it would for any page you open.

It only reads. Nothing on Canvas is changed or submitted.

It can reach only the sites you allow when you connect it: your school's Canvas, Canvas's file storage and your library.

To stop, remove the add-on. To delete what was copied, delete the class's Canvas folder in your library.